Using promises with AngularJS

Question

I have this service

   service.getCurrentUser = function () {
        var def = $q.defer(); 
        if (service.user == null)
        {
            $http.get("./api/GetCurrentUser/")
            .success(function(data) { 
                service.user=data; 
                def.resolve(data); 
            }) 
            .error(function() { 
                def.reject("Failed to get user"); 
            }); 
        }
        else
            def.resolve(service.user);              
        return def.promise;
    }

in my controller I want to call this and wait for return then if the user is in a certain group run other code

How do I write it so it uses the promise returned by the service

What's the name of the service? Where do you inject and call this method? Are you facing any problem? Please create a [mcve]. — 31piy, Aug 24 '18 at 13:12
You mean you want to run some code after the Promise has been resolved? Use `.then`: `YourService.getCurrentUser().then(function(response){...}, function(error){...})` — Aleksey Solovey, Aug 24 '18 at 13:13
`$http.get` already returns a promise; you should use that instead of creating a separate one. https://stackoverflow.com/questions/23803743/what-is-the-explicit-promise-construction-antipattern-and-how-do-i-avoid-it — SLaks, Aug 24 '18 at 13:39

score 0 · Answer 1 · answered Aug 24 '18 at 13:47

The promise implementation can be like:

service.getCurrentUser = function () {
    return new Promise((resolve,reject)=>{
        if (service.user == null) {
            $http.get("./api/GetCurrentUser/")
                .success(function (data) {
                    service.user = data;
                    resolve(data);
                })
                .error(function () {
                    reject("Failed to get user");
                });
        }else{
            resolve(service.user);
        }
    });
}

You can call it as:

    service.getCurrentUser()
    .then(user => {
        console.log('user', user);
    })
    .catch(error => { 
        console.log('error', error);
    });

Using promises with AngularJS

1 Answers1